According to the BankingMyWay Weekly Mortgage Rate Tracker , 30-year fixed rate mortgages shot up again last week to 4.63% from 4.46%. In May and June, mortgages rates shot to 4.6% from around 3.5% in the past 60 days, to the highest levels since 2011, costing new homebuyers a fortune in the process.

"Even with limited choices, it appears some of the rise in contract signings we're seeing could be from buyers wanting to take advantage of current affordability conditions before mortgage interest rates move higher," he says. "This implies a continuation of double-digit price increases from a year earlier, with a strong push from pent-up demand."